Characteristics of Persons Screened for Lung Cancer in the United States : A Cohort Study

Incidentally Detected Lung Cancer in Persons Too Young or Too Old for Lung Cancer Screening in a Mississippi Delta Cohort

INTRODUCTION

Lung cancer risk in screening age-ineligible persons with incidentally detected lung nodules is poorly characterized. We evaluated lung cancer risk in two age-ineligible Lung Nodule Program (LNP) cohorts.

METHODS

Prospective observational study comparing 2-year cumulative lung cancer diagnosis risk, lung cancer characteristics, and overall survival between low-dose computed tomography (LDCT) screening participants aged 50 to 80 years and LNP participants aged 35 to younger than 50 years (young) and older than 80 years (elderly).

RESULTS

From 2015 to 2022, lung cancer was diagnosed in 329 (3.43%), 39 (1.07%), and 172 (6.87%) LDCT, young, and elderly LNP patients, respectively. The 2-year cumulative incidence was 3.0% (95% confidence intervals [CI]: 2.6%-3.4%) versus 0.79% (CI: 0.54%-1.1%) versus 6.5% (CI: 5.5%-7.6%), respectively, but lung cancer diagnosis risk was similar between young LNP and Lung CT Screening Reporting and Data System (Lung-RADS) 1 (adjusted hazard ratio [aHR] = 0.88 [CI: 0.50-1.56]) and Lung-RADS 2 (aHR = 1.0 [0.58-1.72]). Elderly LNP risk was greater than Lung-RADS 3 (aHR = 2.34 [CI: 1.50-3.65]), but less than 4 (aHR = 0.28 [CI: 0.22-0.35]). Lung cancer was stage I or II in 62.92% of LDCT versus 33.33% of young (p = 0.0003) and 48.26% of elderly (p = 0.0004) LNP cohorts; 16.72%, 41.03%, and 29.65%, respectively, were diagnosed at stage IV. The aggregate 5-year overall survival rates were 57% (CI: 48-67), 55% (CI: 39-79), and 24% (CI: 15-40) (log-rank p < 0.0001). Results were similar after excluding persons with any history of cancer.

CONCLUSIONS

LNP modestly benefited persons too young or old for screening. Differences in clinical characteristics and outcomes suggest differences in biological characteristics of lung cancer in these three patient cohorts.

Study rationale and design of the PEOPLHE trial

PURPOSE

Lung cancer screening (LCS) by low-dose computed tomography (LDCT) demonstrated a 20-40% reduction in lung cancer mortality. National stakeholders and international scientific societies are increasingly endorsing LCS programs, but translating their benefits into practice is rather challenging. The "Model for Optimized Implementation of Early Lung Cancer Detection: Prospective Evaluation Of Preventive Lung HEalth" (PEOPLHE) is an Italian multicentric LCS program aiming at testing LCS feasibility and implementation within the national healthcare system. PEOPLHE is intended to assess (i) strategies to optimize LCS workflow, (ii) radiological quality assurance, and (iii) the need for dedicated resources, including smoking cessation facilities.

METHODS

PEOPLHE aims to recruit 1.500 high-risk individuals across three tertiary general hospitals in three different Italian regions that provide comprehensive services to large populations to explore geographic, demographic, and socioeconomic diversities. Screening by LDCT will target current or former (quitting < 10 years) smokers (> 15 cigarettes/day for > 25 years, or > 10 cigarettes/day for > 30 years) aged 50-75 years. Lung nodules will be volumetric measured and classified by a modified PEOPLHE Lung-RADS 1.1 system. Current smokers will be offered smoking cessation support.

CONCLUSION

The PEOPLHE program will provide information on strategies for screening enrollment and smoking cessation interventions; administrative, organizational, and radiological needs for performing a state-of-the-art LCS; collateral and incidental findings (both pulmonary and extrapulmonary), contributing to the LCS implementation within national healthcare systems.

What Goes into Patient Selection for Lung Cancer Screening? Factors Associated with Clinician Judgments of Suitability for Screening

Rationale: Achieving the net benefit of lung cancer screening (LCS) depends on optimizing patient selection. Objective: To identify factors associated with clinician assessments that a patient was unlikely to benefit from LCS ("LCS-inappropriate") because of comorbidities or limited life expectancy. Methods: Retrospective analysis of patients assessed for LCS at 30 Veterans Health Administration facilities from January 1, 2015 to February 1, 2021. We conducted hierarchical mixed-effects logistic regression analyses to determine factors associated with clinicians' designations of LCS inappropriateness (primary outcome), accounting for 3-year predicted probability (i.e., competing risk) of non-lung cancer death. Measurements and Main Results: Among 38,487 LCS-eligible patients, 1,671 (4.3%) were deemed LCS-inappropriate by clinicians, whereas 4,383 (11.4%) had an estimated 3-year competing risk of non-lung cancer death greater than 20%. Patients with higher competing risks of non-lung cancer death were more likely to be deemed LCS-inappropriate (odds ratio [OR], 2.66; 95% confidence interval [CI], 2.32-3.05). Older patients (ages 75-80; OR, 1.45; 95% CI, 1.18-1.78) and those with interstitial lung disease (OR, 1.98; 95% CI, 1.51-2.59) were more likely to be deemed LCS-inappropriate than would be explained by competing risk of non-lung cancer death, whereas patients currently smoking (OR, 0.65; 95% CI, 0.58-0.73) were less likely to be deemed LCS-inappropriate, suggesting that clinicians over- or underweighted these factors. The probability of being deemed LCS-inappropriate varied from 0.4% to 74%, depending on the clinician making the assessment (median OR, 3.07; 95% CI, 2.89-3.25). Conclusion: Concerningly, the likelihood that a patient is deemed LCS-inappropriate is more strongly associated with the clinician making the assessment than with patient characteristics. Patient selection may be optimized by providing decision support to help clinicians assess net LCS benefit.

Emerging Strategies in Lung Cancer Screening: Blood and Beyond

BACKGROUND

Although low dose computed tomography (LDCT)-based lung cancer screening (LCS) can decrease lung cancer-related mortality among high-risk individuals, it remains an imperfect and substantially underutilized process. LDCT-based LCS may result in false-positive findings, which can lead to invasive procedures and potential morbidity. Conversely, current guidelines may fail to capture at-risk individuals, particularly those from under-represented minority populations. To address these limitations, numerous biomarkers have emerged to complement LDCT and improve early lung cancer detection.

CONTENT

This review focuses primarily on blood-based biomarkers, including protein, microRNAs, circulating DNA, and methylated DNA panels, in current clinical development for LCS. We also examine other emerging biomarkers-utilizing airway epithelia, exhaled breath, sputum, and urine-under investigation. We highlight challenges and limitations of biomarker testing, as well as recent strategies to integrate molecular strategies with imaging technologies.

SUMMARY

Multiple biomarkers are under active investigation for LCS, either to improve risk-stratification after nodule detection or to optimize risk-based patient selection for LDCT-based screening. Results from ongoing and future clinical trials will elucidate the clinical utility of biomarkers in the LCS paradigm.

Comparing Lung Cancer Screening Strategies in a Nationally Representative US Population Using Transportability Methods for the National Lung Cancer Screening Trial

Importance

The National Lung Screening Trial (NLST) found that screening for lung cancer with low-dose computed tomography (CT) reduced lung cancer-specific and all-cause mortality compared with chest radiography. It is uncertain whether these results apply to a nationally representative target population.

Objective

To extend inferences about the effects of lung cancer screening strategies from the NLST to a nationally representative target population of NLST-eligible US adults.

Design, Setting, and Participants

This comparative effectiveness study included NLST data from US adults at 33 participating centers enrolled between August 2002 and April 2004 with follow-up through 2009 along with National Health Interview Survey (NHIS) cross-sectional household interview survey data from 2010. Eligible participants were adults aged 55 to 74 years, and were current or former smokers with at least 30 pack-years of smoking (former smokers were required to have quit within the last 15 years). Transportability analyses combined baseline covariate, treatment, and outcome data from the NLST with covariate data from the NHIS and reweighted the trial data to the target population. Data were analyzed from March 2020 to May 2023.

Interventions

Low-dose CT or chest radiography screening with a screening assessment at baseline, then yearly for 2 more years.

Main Outcomes and Measures

For the outcomes of lung-cancer specific and all-cause death, mortality rates, rate differences, and ratios were calculated at a median (25th percentile and 75th percentile) follow-up of 5.5 (5.2-5.9) years for lung cancer-specific mortality and 6.5 (6.1-6.9) years for all-cause mortality.

Results

The transportability analysis included 51 274 NLST participants and 685 NHIS participants representing the target population (of approximately 5 700 000 individuals after survey-weighting). Compared with the target population, NLST participants were younger (median [25th percentile and 75th percentile] age, 60 [57 to 65] years vs 63 [58 to 67] years), had fewer comorbidities (eg, heart disease, 6551 of 51 274 [12.8%] vs 1 025 951 of 5 739 532 [17.9%]), and were more educated (bachelor's degree or higher, 16 349 of 51 274 [31.9%] vs 859 812 of 5 739 532 [15.0%]). In the target population, for lung cancer-specific mortality, the estimated relative rate reduction was 18% (95% CI, 1% to 33%) and the estimated absolute rate reduction with low-dose CT vs chest radiography was 71 deaths per 100 000 person-years (95% CI, 4 to 138 deaths per 100 000 person-years); for all-cause mortality the estimated relative rate reduction was 6% (95% CI, -2% to 12%). In the NLST, for lung cancer-specific mortality, the estimated relative rate reduction was 21% (95% CI, 9% to 32%) and the estimated absolute rate reduction was 67 deaths per 100 000 person-years (95% CI, 27 to 106 deaths per 100 000 person-years); for all-cause mortality, the estimated relative rate reduction was 7% (95% CI, 0% to 12%).

Conclusions and Relevance

Estimates of the comparative effectiveness of low-dose CT screening compared with chest radiography in a nationally representative target population were similar to those from unweighted NLST analyses, particularly on the relative scale. Increased uncertainty around effect estimates for the target population reflects large differences in the observed characteristics of trial participants and the target population.

Adherence to Annual Lung Cancer Screening in a Centralized Academic Program

BACKGROUND

Adherence to lung cancer screening (LCS) protocols is critical for achieving mortality reductions. However, adherence rates, particularly for recommended annual screening among patients with low-risk findings, are often sub-optimal. We evaluated annual LCS adherence for patients with low-risk findings participating in a centralized screening program at a tertiary academic center.

PATIENTS AND METHODS

We conducted a retrospective, observational cohort study of a centralized lung cancer screening program launched in July 2018. We performed electronic medical review of 337 patients who underwent low-dose CT (LDCT) screening before February 1, 2021 (to ensure ≥ 15 months follow up) and had a low-risk Lung-RADS score of 1 or 2. Captured data included patient characteristics (smoking history, Fagerstrom score, environmental exposures, lung cancer risk score), LDCT imaging dates, and Lung-RADS results. The primary outcome measure was adherence to annual screening. We used multivariable logistic regression models to identify factors associated with adherence.

RESULTS

Overall, 337 patients had an initial Lung-RADS result of 1 (n = 189) or 2 (n = 148). Among this cohort, 139 (73.5%) of Lung-RADS 1 and 111 (75.0%) of Lung-RADS 2 patients completed the annual repeat LDCT within 15 months, respectively. The only patient characteristic associated with adherence was having Medicaid coverage; compared to having private insurance, Medicaid patients were less adherent (adjusted OR = 0.37, 95% CI = 0.15-0.92). No other patient characteristic was associated with adherence.

CONCLUSION

Our centralized screening program achieved a high initial annual adherence rate. Although LCS has first-dollar insurance coverage, other socioeconomic concerns may present barriers to annual screening for Medicaid recipients.

Promoting lung cancer screening of high-risk patients by primary care providers

BACKGROUND

Lung cancer screening (LCS) with low-dose computed tomography (LDCT) of the chest of eligible patients remains low. Accordingly, augmentation of appropriate LCS referrals by primary care providers (PCPs) was sought.

METHODS

The quality improvement (QI) project was performed between April 2021 and June 2022. It incorporated patient education, shared decision-making (SDM) with PCPs, and tracking of initial LDCT completion. In each case, lag time (LT) to LCS and pack-years (PYs) were calculated from initial LCS eligibility. The cohort's scores were compared to national scores. Patient zip codes were used to create a geographic map of our cohort for comparison with public health data.

RESULTS

An immediate and sustained increase in weekly LCS referrals from PCPs was recorded. Of 337 initial referrals, 95% were men, consisting of 66.2% Black, 28.4% White, and 5.4% other. Mean PY was less for minorities (45.3 vs. 37.3 years; p = .0002) but mean LT was greater for Whites (7.9 vs. 6.2 years; p = .03). Twenty-five percent of veterans failed to report to their scheduled screening, and two declined referrals. Notably, most no-show patients lived in transit deserts. Furthermore, Lung-RADS scores 4B/4X were more than double the expected prevalence (p = .008).

CONCLUSIONS

The PCPs in this study successfully augmented LCS referrals. A substantial proportion of these patients were no-shows, and our data suggest complex racial and socioeconomic factors as contributing variables. In addition, a higher-than-expected number of initial Lung-RADS scores 4B/4X were reported. A large, multisite QI project is warranted to address overcoming potential transportation barriers in high-risk patient populations.

Changes in Stage at Presentation among Lung and Breast Cancer Patients During the COVID-19 Pandemic

BACKGROUND

The COVID-19 pandemic altered access to healthcare by decreasing the number of patients able to receive preventative care and cancer screening. We hypothesized that, given these changes in access to care, radiologic screening for breast and lung cancer would be decreased, and patients with these cancers would consequently present at later stages of their disease.

STUDY DESIGN

This is a retrospective cross-sectional study of 2017 to September 2021 UMass Memorial Tumor Registry data for adult breast and lung cancer patients. Changes in stage at presentation of breast and lung cancer during the COVID-19 pandemic were measured, defined as before and during COVID-19.

RESULTS

There were no statistically significant changes in the overall stage of presentation before or during the COVID-19 pandemic for either breast or lung cancer patients. Analysis of case presentation and stage during periods of COVID-19 surges that occurred during the time of this study compared with prepandemic data demonstrated a statistically significant decrease in overall presentation of breast cancer patients in the first surge, with no other statistically significant changes in breast cancer presentation. A nonstatistically significant decrease in lung cancer presentation was seen during the initial surge of COVID-19. There was also a statistically significant increase in early-stage presentation of lung cancer during the second and third COVID-19 surges.

CONCLUSIONS

In the 2 years after the COVID-19 pandemic, we were not able to demonstrate stage migration at presentation of breast and lung cancer patients to later stages despite decreases in overall presentation during the initial 2 years of the COVID pandemic. An increase in early-stage lung cancer during the second and third surges is interesting and could be related to increased chest imaging for COVID pneumonia.

A Closer Look-Who Are We Screening for Lung Cancer?

Objective

To evaluate the characteristics of individuals receiving lung cancer screening (LCS) and identify those with potentially limited benefit owing to coexisting chronic illnesses and/or comorbidities.

Patients and Methods

In this retrospective study in the United States, patients were selected from a large clinical database who received LCS from January 1, 2019, through December 31, 2019, with at least 1 year of continuous enrollment. We assessed for potentially limited benefit in LCS defined strictly as not meeting the traditional risk factor inclusion criteria (age <55 years or >80 years, previous computed tomography scan within 11 months before an LCS examination, or a history of nonskin cancer) or liberally as having the potential exclusion criteria related to comorbid life-limiting conditions, such as cardiac and/or respiratory disease.

Results

A total of 51,551 patients were analyzed. Overall, 8391 (16.3%) individuals experienced a potentially limited benefit from LCS. Among those who did not meet the strict traditional inclusion criteria, 317 (3.8%) were because of age, 2350 (28%) reported a history of nonskin malignancy, and 2211 (26.3%) underwent a previous computed tomography thorax within 11 months before an LCS examination. Of those with potentially limited benefit owing to comorbidity, 3680 (43.9%) were because of severe respiratory comorbidity (937 [25.5%] with any hospitalization for coronary obstructive pulmonary disease, interstitial lung disease, or respiratory failure; 131 [3.6%] with hospitalization for respiratory failure requiring mechanical ventilation; or 3197 [86.9%] with chronic obstructive disease/interstitial lung disease requiring outpatient oxygen) and 721 (8.59%) with cardiac comorbidity.

Conclusion

Up to 1 of 6 low-dose computed tomography examinations may have limited benefit from LCS.

Home-based self-sampling vs clinician sampling for anal precancer screening: The Prevent Anal Cancer Self-Swab Study

Sexual minority men are at increased risk for anal squamous cell carcinoma. Our objective was to compare screening engagement among individuals randomized to self-collect an anal canal specimen at home or to attend a clinic appointment. Specimen adequacy was then assessed for human papillomavirus (HPV) DNA genotyping. A randomized trial recruited cisgendered sexual minority men and transgender people in the community and assigned them to use a home-based self-collection swabbing kit or attend a clinic-based swabbing. Swabs were sent for HPV genotyping. The proportions of participants completing screening in each study arm and the adequacy of their specimens for HPV genotyping were assessed. Relative risks were estimated for factors associated with screening. A total of 240 individuals were randomized. Age (median, 46 years) and HIV status (27.1% living with HIV) did not differ by study arm. A total of 89.2% and 74.2% of home-arm and clinic-arm individuals returned the swab, respectively (P = .003), difference between groups, 15.0% (95% CI 5.4%-24.6%). Among black individuals, 96.2% and 63.2% in the home and clinic arms screened (P = .006). Among individuals with HIV, 89.5% and 51.9% in the home and clinic arms screened (P < .001). Self-collected swabs and clinician-collected swabs were comparable in adequacy for HPV genotyping (96.3% and 93.3%, respectively). People at highest risk for anal cancer may be more likely to screen if they are able to self-collect swabs at home rather than attend a clinic.

Expanding the Reach and Grasp of Lung Cancer Screening

Low-dose computer tomographic (LDCT) lung cancer screening reduces lung cancer-specific and all-cause mortality among high-risk individuals, but implementation has been challenging. Despite health insurance coverage for lung cancer screening in the United States since 2015, fewer than 10% of eligible persons have participated; striking geographic, racial, and socioeconomic disparities were already evident, especially in the populations at greatest risk of lung cancer and, therefore, most likely to benefit from screening; and adherence to subsequent testing is significantly lower than that reported in clinical trials, potentially reducing the realized benefit. Lung cancer screening is a covered health care benefit in very few countries. Obtaining the full population-level benefit of lung cancer screening will require improved participation of already eligible persons (the grasp of screening) and improved eligibility criteria that more closely match up with the full spectrum of persons at risk (the reach of screening), irrespective of smoking history. We used the socioecological framework of health care to systematically review implementation barriers to lung cancer screening and discuss multilevel solutions. We also discussed guideline-concordant management of incidentally detected lung nodules as a complementary approach to early lung cancer detection that can extend the reach and strengthen the grasp of screening. Furthermore, we discussed ongoing efforts in Asia to explore the possibility of LDCT screening in populations in whom lung cancer risk is relatively independent of smoking. Finally, we summarized innovative technological solutions, including biomarker selection and artificial intelligence strategies, to improve the safety, effectiveness, and cost-effectiveness of lung cancer screening in diverse populations.

Lung Cancer Screening

Lung cancer is a leading cause of cancer death in the United States and globally with the majority of lung cancer cases attributable to cigarette smoking. Given the high societal and personal cost of a diagnosis of lung cancer including that most cases of lung cancer when diagnosed are found at a late stage, work over the past 40 years has aimed to detect lung cancer earlier when curative treatment is possible. Screening trials using chest radiography and sputum failed to show a reduction in lung cancer mortality however multiple studies using low dose CT have shown the ability to detect lung cancer early and a survival benefit to those screened. This review will discuss the history of lung cancer screening, current recommendations and screening guidelines, and implementation and components of a lung cancer screening program.